[Technical Field]
[0001] The present invention relates to a high-pressure fluid discharge device.
[Background Art]
[0003] High-pressure fluid discharge devices are used for, for example, decontamination/disassembly
processes of nuclear reactor power generation facilities, and so on. The high-pressure
fluid discharge devices can spray high pressure fluids onto objects to perform cleaning,
cutting, chipping of concrete (removal of a contaminated surface layer), and so on
of pipes, metallic structures, tanks, and so on. Patent Document 1 discloses a peening
device in a nuclear reactor which performs shot peening, water jet peening, etc. on
a surface of structures inside the nuclear reactor as one of such high-pressure fluid
discharge devices.
[Citation List]
[Patent Document]
[Patent Document 1]
[0004] Japanese Unexamined Patent Application, First Publication No.
2000-298189
[Summary of Invention]
[Technical Problem]
[0005] In nuclear reactor power generation facilities, for example, there are a plurality
of structural members in the facilities. For this reason, pipes configured to transfer
high pressure fluids need to be routed while avoiding the plurality of structural
members to spray the high pressure fluids onto objects. As a result, the pipes are
elongated, and a pressure drop while the high pressure fluids are transferred is increased
so that it may become impossible to spray the fluids onto the objects at high pressure.
[0006] In this case, although a usage of pipes having large flow passage areas is considered,
diameters of the pipes having the large flow passage areas are large and thus the
routing thereof is not easily performed. For this reason, for example, usage of a
bent pipe, an elbow, and so on is required and thus installing the pipes takes a long
time. Also, when discharge positions of the high pressure fluids are changed, moving
the pipes becomes difficult with this installation. Thus, the degree of freedom may
be degraded.
[0007] The present invention was made in view of the above-described problems, and an object
of the present invention is to provide a high-pressure fluid discharge device capable
of easily routing a pipe while suppressing the pressure drop of a high pressure fluid.
[Solution to Problem]
[0008] In order to solve the above problems, according to a first aspect of the present
invention, there is provided a high-pressure fluid discharge device in which a pipe,
to which a nozzle is connected, is routed and a high pressure fluid transferred through
the pipe is discharged from the nozzle, wherein the pipe is formed by alternately
connecting first pipes and second pipes having a larger flow passage area than the
first pipes.
[0009] According to a second aspect of the present invention, in the first aspect, the first
pipes are formed in expandable coil shapes.
[0010] According to a third aspect of the present invention, in the first or second aspect,
at least one of the second pipes is connected to one of the first pipes formed in
the coil shape in a tangential direction of the first pipes.
[0011] According to a fourth aspect of the present invention, in the first to third aspects,
the second pipes are longer than the first pipes.
[0012] According to a fifth aspect of the present invention, in the first to fourth aspects,
the first pipes and the second pipes are formed of stainless steel.
[0013] According to a sixth aspect of the present invention, in the first to fifth aspects,
the high pressure fluid is liquid nitrogen.
[0014] According to the present invention, a pipe, to which a nozzle configured to discharge
a high pressure fluid is connected, is configured to transfer the high pressure fluid
is formed by alternately connecting first pipes and second pipes having a larger flow
passage area than the first pipes. The pressure drop while the high pressure fluid
is transferred is suppressed by increasing the flow passage area using the second
pipes and thus the pipe can be routed farther. Also, the first pipes having the smaller
flow passage areas than the second pipes are allowed to be freely bent at required
points of the pipe so that a degree of freedom of the routing of the entire pipe can
be increased.
[0015] Therefore, according to the present invention, the high-pressure fluid discharge
device capable of easily routing the pipe while suppressing the pressure drop of the
high pressure fluid is acquired.
[Brief Description of Drawings]
[0016]
FIG. 1 is a view showing an overall constitution of a high-pressure fluid discharge
device in an embodiment of the present invention.
FIG. 2 is a configuration diagram of a pipe in the embodiment of the present invention.
FIG. 3 is a cross-sectional configuration diagram of a pipe joint in the embodiment
of the present invention.
FIG. 4 is a graph showing a relationship between a length of the pipe and a pressure
drop in the embodiment of the present invention.
FIG. 5A is a perspective view of a pipe in another embodiment of the present invention.
FIG. 5B is a perspective view of a pipe in another embodiment of the present invention.
FIG. 6A is a side view of a pipe in still another embodiment of the present invention.
FIG. 6B is a side view of a pipe in yet another embodiment of the present invention.
[Description of Embodiments]
[0017] Hereinafter, embodiments of the present invention will be described with reference
to the drawings.
[0018] FIG. 1 is a view showing an overall constitution of a high-pressure fluid discharge
device 1 in an embodiment of the present invention.
[0019] As shown in FIG. 1, in the high-pressure fluid discharge device 1, a pipe 31, to
which a nozzle 40 is connected, is routed, and a high pressure fluid transferred through
the pipe 31 is discharged from the nozzle 40. To be specific, the high-pressure fluid
discharge device 1 in the embodiment performs chipping on a decontamination object
wall X of a nuclear power generation facility (removal of a contaminated surface layer),
and so on.
[0020] The high-pressure fluid discharge device 1 includes a storage tank 10, a pressurizing
device 20, a cooling device 30, the nozzle 40, and a vacuum suction device 50.
[0021] The storage tank 10 stores a fluid discharged from the nozzle 40. The fluid in the
embodiment is cryogenic liquid nitrogen. Liquid nitrogen can reduce processing cost
without secondary contamination because it is vaporized at room temperature and does
not generate contaminated water when used like a water jet. The storage tank 10 is
connected to the pressurizing device 20 via a pipe 11.
[0022] The pressurizing device 20 pressurizes the fluid transferred through the pipe 11
from the storage tank 10. The pressurizing device 20 in the embodiment generates,
for example, a high pressure fluid at several hundred MPa (megapascals). For example,
a reciprocating volume compressor can be used as the pressurizing device 20. Another
type of pressurizing device 20 can be adopted according to a type of discharged high
pressure fluid, and for example, a turbo compressor can also be used. The pressurizing
device 20 is connected to the cooling device 30 via a pipe 21.
[0023] The cooling device 30 cools the high pressure fluid transferred through the pipe
21 from the pressurizing device 20. The cooling device 30 includes a heat exchanger
configured to decrease a temperature of a high pressure fluid whose temperature is
increased due to the pressurizing device 20. The cooling device 30 in the embodiment
is connected to an operation board 30a and controls a supplied amount and so on, of
a refrigerant exchanging heat with a high pressure fluid so that the temperature of
the high pressure fluid can be decreased to a set temperature. The cooling device
30 is connected to the nozzle 40 via the pipe 31.
[0024] The nozzle 40 discharges the high pressure fluid transferred through the pipe 31
from the cooling device 30 toward the decontamination object wall X. The nozzle 40
is surrounded by a nozzle shroud 41. The nozzle shroud 41 is formed substantially
in a box shape which is opened in a discharge direction of the high pressure fluid
and forms a space surrounding a discharge region of the high pressure fluid by bringing
an open end thereof into contact with the decontamination object wall X. A pipe 51
is connected to the nozzle shroud 41.
[0025] The vacuum suction device 50 suctions a fluid inside the nozzle shroud 41 via the
pipe 51. The vacuum suction device 50 is configured to suction the high pressure fluid
discharged toward the decontamination object wall X and the contaminated surface layer
of the decontamination object wall X removed by the high pressure fluid. A solid (a
surface layer, etc. of the decontamination object wall X) included in the fluid suctioned
through the vacuum suction device 50 is transferred via a pipe 52 and is recovered
by a filter 53. The fluid (a gas) passing through the filter 53 is transferred through
a pipe 54 and is exhausted through a blower 55. Note that, in the embodiment, the
exhausted gas is nitrogen gas, which does not affect the environment.
[0026] Next, a constitution of the pipe 31 configured to connect the cooling device 30 with
the nozzle 40 will be described.
[0027] As shown in FIG. 1, the cooling device 30 in the embodiment is in an operation room
serving as a non-contaminated area, and the decontamination object wall X is in an
object room of decontamination serving as a contaminated area. Since there is a plurality
of structural members (not shown) in a contaminated area of a nuclear reactor power
generation facility, for example, the pipe 31 needs to be routed to bypass the plurality
of structures.
[0028] FIG. 2 is a configuration diagram of the pipe 31 in the embodiment of the present
invention.
[0029] As shown in FIG. 2, the pipe 31 is formed by alternately connecting first pipes 31a
and second pipes 31b having a larger flow passage area than the first pipes 31a. The
first pipes 31a and the second pipes 31b are formed of stainless steel capable of
transferring liquid nitrogen serving as a cryogenic high pressure fluid, and flow
passage areas of which are increased according to the diameters.
[0030] The first pipes 31a each have a first diameter D1. The second pipes 31b each have
a second diameter D2 larger than the first diameter D1. The first diameter D1 of the
first pipe 31a in the embodiment is set to, for example, 1/4 inch. Also, the second
diameter D2 of the second pipe 31b in the embodiment is set to, for example, 3/8 inch.
The first pipe 31a and the second pipe 31b having different diameters are connected
via a pipe joint 32. The pipe joint 32 is also formed of stainless steel.
[0031] FIG. 3 is a cross-sectional configuration diagram of a pipe joint in the embodiment
of the present invention.
[0032] The pipe joint 32 includes a joint main body 33 configured to abut the first pipe
31a and the second pipe 31b. The joint main body 33 includes a first flow passage
34a having the same flow passage area as the first pipe 31a, a second flow passage
34b having the same flow passage area as the second pipe 31b, and a taper flow passage
34c configured to gently connect the first flow passage 34a with the second flow passage
34b. The first pipe 31a is caulked by a front ferrule 36a and a back ferrule 37a incorporated
between the joint main body 33 and a nut 35a, and is fixed to the pipe joint 32. In
addition, the second pipe 31b is caulked by a front ferrule 36b and a back ferrule
37b incorporated between the joint main body 33 and a nut 35b, and is fixed to the
pipe joint 32.
[0033] As shown in FIG. 2, a length of the second pipe 31b is set to be longer than that
of the first pipe 31a. The first pipe 31a has a length L1. The length L1 of the first
pipe 31a in the embodiment is set to, for example, 5 m (meters). Also, the second
pipe 31b has a length L2. The length L2 of the second pipe 31b in the embodiment is
set to, for example, 20 m. For example, when the pipe 31 is routed by 100 m or more,
at least four first pipes 31a and at least four second pipes 31b may be alternately
connected.
[0034] FIG. 4 is a graph showing a relationship between a length of the pipe and a pressure
drop in the embodiment of the present invention.
[0035] In FIG. 4, the vertical axis represents pressure, and the horizontal axis represents
length. Also, in FIG. 4, a solid line indicates a state of a pressure drop when the
entire diameter of the pipe 31 is set to 1/4 inch, and a dotted line indicates the
state of a pressure drop when the entire diameter of the pipe 31 is set to 3/8 inch.
[0036] As shown in FIG. 4, it can be seen that a pressure obtained by pressurizing up to
350 Mpa is zero at a point of 80 m when the entire diameter of the pipe 31 is set
to 1/4 inch. On the other hand, it can be seen that the pressure obtained by pressurizing
is maintained at a high value even at a point of 100 m when the entire diameter of
the pipe 31 is set to 3/8 inch. As described above, in the pipe 31, it can be seen
that setting of the second pipe 31b to be longer than the first pipe 31a is effective
in view of suppression of the pressure drop.
[0037] Referring again to FIG. 2, the first pipe 31a is formed in an expandable coil shape.
On the other hand, the second pipe 31b is formed in a linear shape. To be specific,
the first pipe 31a is formed in the expandable coil shape in a longitudinal direction
of the second pipe 31b. In FIG. 2, the first pipe 31a is formed by winding a tube
with a coil shape a plurality of times in the longitudinal direction of the second
pipe 31b. Also, the first pipe 31a can also be bent in the longitudinal direction
of the second pipe 31b.
[0038] In the high-pressure fluid discharge device 1 with the above-described constitution,
the pipe 31, to which the nozzle 40 configured to discharge the high pressure fluid
is connected, is formed by alternately connecting the first pipes 31a and the second
pipes 31b having the larger flow passage area than the first pipes 31a as shown in
FIG. 2. As the second pipes 31b are connected, and the flow passage area is increased,
the pressure drop while the high pressure fluid is transferred is suppressed in comparison
to, for example, when the entire diameter of the pipe 31 is set to 1/4 inch as apparent
from the tendency shown in FIG. 4. For this reason, in the embodiment, in FIG. 1 as
an example, for example, the pipe 31 can be routed from the operation room to the
decontamination object wall X which is 100 m or more away from the operation room
while the pressure drop of the high pressure fluid is suppressed.
[0039] The first pipes 31a having smaller flow passage areas than the second pipes 31b are
alternately connected and are allowed to be freely bent at required points of the
pipe 31 so that a degree of freedom of the routing of the entire pipe 31 can be increased.
Therefore, in the embodiment, even if multiple bends are required in the contaminated
area, the pipe 31 can be easily routed.
[0040] Also, in the embodiment, since the first pipe 31a is formed in the expandable coil
shape, the first pipe 31a can be expanded according to step differences in the contaminated
area and shapes of the structural members. In addition, since a bent position of the
pipe 31 can be easily changed, the pipe 31 can be more simply routed. Therefore, in
the embodiment, the pipe 31 is easily laid, a construction time is shortened, and
a position of the laid pipe 31 can be easily changed.
[0041] Also, in the embodiment, since the second pipe 31b is longer than the first pipe
31a, the pressure drop of the high pressure fluid can be effectively suppressed in
comparison to the opposite case in which the first pipe 31a is longer as apparent
from the tendency shown in FIG. 4.
[0042] FIGS. 5A and 5B are perspective views of the pipe 31 in another embodiment of the
present invention. FIG. 5A shows a state in which the first pipe 31a is contracted,
and FIG. 5B shows a state in which the first pipe 31a is extended. The remaining constitution
of the high-pressure fluid discharge device 1 is the same as the embodiment shown
in FIG. 2.
[0043] As shown in FIGS. 5A and 5B, the first pipe 31a is formed in a coil shape in a direction
different from the longitudinal direction of the second pipes 31b (a direction indicated
by a dotted arrow in FIG. 5B. Hereinafter referred to as an "expansion and contraction
direction"), and has an expandable constitution within an expansion and contraction
width H1 to H2 in the expansion and contraction direction. In FIGS. 5A and 5B, the
first pipe 31a is formed by winding a tube with a coil shape a plurality of times
in the expansion and contraction direction.
[0044] Also, shown in FIGS. 5A and 5B, at least one of the second pipes 31b may be connected
to the first pipe 31a in a tangential direction T of the first pipe 31a formed in
the coil shape.
[0045] Even in the embodiments shown in FIGS. 5A and 5B, the first pipe 31a having the smaller
flow passage area than the second pipe 31b can be freely bent while the pressure drop
of the high pressure fluid is effectively suppressed as in the embodiment shown in
FIG. 2 so that a degree of freedom of the routing of the entire pipe 31 can be increased.
Also, as shown in FIGS. 5A and 5B, the at least one of the second pipes 31b is connected
to the first pipe 31a at a required point such as a step difference in the tangential
direction T of the first pipe 31a formed in the coil shape so that the high pressure
fluid can be transferred without reducing its flow force. For this reason, the pressure
drop of the high pressure fluid can be effectively suppressed compared with, for example,
the connection method shown in FIG. 2. In other words, in the connection method shown
in FIG. 2, a coil start portion of the first pipe 31a is bent substantially at a right
angle at a steep angle in the longitudinal direction of the second pipe 31b. On the
other hand, in the connection method shown in FIGS. 5A and 5B, the coil start portions
of the first pipe 31a are gently bent in the tangential direction T of the coil in
the longitudinal direction of the second pipe 31b. As a result, in the connection
method of FIGS. 5A and 5B, the flow force of the high pressure fluid flowing from
the second pipe 31b is less likely to be reduced at the coil start portion compared
with the connection method shown in FIG. 2, and thus the pressure drop of the high
pressure fluid at this portion is effectively suppressed.
[0046] In the examples shown in FIGS. 5A and 5B, although the expansion and contraction
direction of the first pipe 31a is substantially perpendicular to the longitudinal
direction of the second pipe 31b, the expansion and contraction direction can be arbitrarily
set according to an installation condition and so on, of the high-pressure fluid discharge
device 1. Also, the first pipe 31a can also be bent in the above-described expansion
and contraction direction.
[0047] FIGS. 6A and 6B are side views of the pipe 31 in still another embodiment of the
present invention. The remaining constitution of the high-pressure fluid discharge
device 1 is the same as the embodiment shown in FIG. 2.
[0048] FIG. 6A shows a case in which second pipes 31b which are substantially perpendicular
to each other are connected by a first pipe 31a formed in a single coil shape. Even
in this case, one of the second pipes 31b is connected to the other of the second
pipes 31b in a tangential direction T of the first pipe 31a.
[0049] Also, FIG. 6B shows a case in which a tube formed in a single coil shape is used
as the pipe 31a in FIGS. 5A and 5B rather than a tube formed by being wound a plurality
of times in an expansion and contraction direction.
[0050] In the embodiments shown in FIGS. 6A and 6B, relative positions (an angle) of the
two second pipes 31b coupled via the first pipe 31a which follow a direction along
a paper surface and a direction perpendicular to the paper surface of the drawings
are changed so that the pipe 31 can be bent.
[0051] Even in the embodiments shown in FIGS. 6A and 6B, the first pipe 31a having the smaller
flow passage area than the second pipes 31b can be freely bent while the pressure
drop of the high pressure fluid is effectively suppressed as in the embodiment shown
in FIG. 2 so that a degree of freedom of the routing of the entire pipe 31 can be
increased. Also, at least one of the second pipes 31b is connected to the first pipe
31a in the tangential direction T of the first pipe 31a formed in the coil shape as
in the embodiments shown in FIGS. 5A and 5B so that the high pressure fluid can be
transferred without reducing the flow force thereof.
[0052] As described above, according to the above-described embodiments, the high-pressure
fluid discharge device 1 in which the pipe 31 can be easily routed while the pressure
drop of the high pressure fluid is suppressed is acquired by adopting a constitution
of the high-pressure fluid discharge device 1 in which the pipe 31, to which the nozzle
40 is connected, is routed and the high pressure fluid transferred through the pipe
31 is discharged from the nozzle 40, in which the pipe 31 is formed by alternately
connecting the first pipes 31a and the second pipes 31b having the larger flow passage
area than the first pipes 31a.
[0053] Although the preferred embodiments of the present invention have been described above
with reference to the drawings, the present invention is not limited to the above-described
embodiments. The various shapes or the combinations of the constituent members in
the embodiments are only examples and can be modified in various forms depending on
design requirements without departing from the gist of the present invention.
[0054] Although, for example, constitutions in which the first pipe 31a is formed in the
coil shape have been described in the above-described embodiments, the present invention
is not limited to such constitutions, and for example, a straight pipe structure in
which the first pipe 31a is formed in a linear shape like the second pipe 31b may
be provided. Even in this case, since the first pipe 31a is relatively thinner and
is deformed easier than the second pipe 31b, the same effect as the above-described
embodiment is acquired.
[0055] Also, although, for example, cases in which the high pressure fluid is liquid nitrogen
have been described in the above-described embodiments, the present invention is not
limited to such constitutions, and the high pressure fluid may be other fluids, for
example, water or oil, other cryogenic liquids, a gas, and so on.
[0056] Also, although, for example, the high-pressure fluid discharge device is used for
decontamination/disassembly of a nuclear reactor power generation facility in the
above-described embodiments, the present invention is not limited to such constitutions,
and the present invention can also be used for, for example, removal of a painting
of a bridge, removal of fouling of a heat exchanger, and so on.
[Industrial Applicability]
[0057] A high-pressure fluid discharge device capable of easily routing pipes while a pressure
drop of a high pressure fluid is suppressed is acquired.
[Reference Signs List]
[0058]
- 1:
- high-pressure fluid discharge device
- 31:
- pipe
- 31a:
- first pipe
- 32b:
- second pipe
- 40:
- nozzle
- T:
- tangential direction